README
¶
go-whosonfirst-placetypes-wasm
Go package for compiling methods from the go-whosonfirst-placetypes package to a JavaScript-compatible WebAssembly (wasm) binary. It also provides a net/http middleware packages for appending the necessary static assets and HTML resources to use the wasm binary in web applications.
Build
To build the validate_feature WebAssembly binary for use in your applications run the following command:
GOOS=js GOARCH=wasm go build -mod vendor -ldflags="-s -w" -o static/wasm/whosonfirst_placetypes.wasm cmd/placetypes/main.go
Use
In order to load the whosonfirst_placetypes functions you will need to include the wasm_exec.js and whosonfirst.placetypes.wasm.js JavaScript files, or functional equivalents. Both scripts are bundled with this package in the static/javascript folder.
Functions
whosonfirst_placetypes
Return a JSON-encoded list of all valid Who's On First placetypes.
whosonfirst_placetypes()
.then((data) => { ... });
whosonfirst_placetypes_ancestors
Return a JSON-encoded list of all the ancestors for a given placetype.
whosonfirst_placetypes_ancestors("region", "common,optional,common_optional")
.then((data) => { ... });
The second argument (a comma-separated list of placetype roles to filter results by) is optional. If absent then the "common" role will be assumed.
whosonfirst_placetypes_children
Return a JSON-encoded list of all the children for a given placetype.
whosonfirst_placetypes_children("region")
.then((data) => { ... });
whosonfirst_placetypes_descendants
Return a JSON-encoded list of all the descendants for a given placetype.
whosonfirst_placetypes_descendants("region", "common,optional,common_optional")
.then((data) => { ... });
The second argument (a comma-separated list of placetype roles to filter results by) is optional. If absent then the "common" role will be assumed.
whosonfirst_placetypes_core
Return success if a placetype is considered to be a "core" Who's On First placetype or throws and error if not.
whosonfirst_placetypes_is_core("region")
.then(() => { console.log("Core"); })
.catch(() => { console.log("Not core"); });
whosonfirst_placetypes_isvalid
Return success if a placetype is valid or throw an error if not.
whosonfirst_placetypes_is_valid("region")
.then(() => { console.log("Valid"); })
.catch(() => { console.log("Invalid"); });
whosonfirst_placetypes_parents
Return a JSON-encoded list of all the parent placetypes for a given placetype.
whosonfirst_placetypes_parents("region")
.then((data) => { ... });
Middleware
The go-whosonfirst-validate-wasm/http package provides methods for appending static assets and HTML resources to existing web applications to facilitate the use of the validate_feature WebAssembly binary. For example:
Note the use of the sfomuseum/go-http-wasm package which is an HTTP middleware package for serving and appending resources to the wasm_exec.js JavaScript library.
package main
import (
"embed"
"flag"
"fmt"
"log"
"net/http"
placetypes_wasm "github.com/whosonfirst/go-whosonfirst-placetypes-wasm/http"
wasm_exec "github.com/sfomuseum/go-http-wasm"
)
//go:embed index.html example.*
var FS embed.FS
func main() {
host := flag.String("host", "localhost", "The host name to listen for requests on")
port := flag.Int("port", 8080, "The host port to listen for requests on")
flag.Parse()
mux := http.NewServeMux()
wasm_exec.AppendAssetHandlers(mux)
placetypes_wasm.AppendAssetHandlers(mux)
http_fs := http.FS(FS)
example_handler := http.FileServer(http_fs)
mux.Handle("/", example_handler)
addr := fmt.Sprintf("%s:%d", *host, *port)
log.Printf("Listening for requests on %s\n", addr)
http.ListenAndServe(addr, mux)
}
Error handling omitted for brevity.
Example
There is a full working example of this application in the cmd/example folder. To run this application type the following command:
$> make example
go run -mod vendor cmd/example/main.go
2023/01/31 15:11:48 Listening for requests on localhost:8080
Then open http://localhost:8080 in a web browser. You should see something like this:
For example:
See also
Documentation
¶
Index ¶
- func AncestorsFunc(spec *placetypes.WOFPlacetypeSpecification) js.Func
- func ChildrenFunc(spec *placetypes.WOFPlacetypeSpecification) js.Func
- func DescendantsFunc(spec *placetypes.WOFPlacetypeSpecification) js.Func
- func IsCoreFunc(spec *placetypes.WOFPlacetypeSpecification) js.Func
- func IsValidFunc(spec *placetypes.WOFPlacetypeSpecification) js.Func
- func ParentsFunc(spec *placetypes.WOFPlacetypeSpecification) js.Func
- func PlacetypesFunc(spec *placetypes.WOFPlacetypeSpecification) js.Func
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func AncestorsFunc ¶
func ChildrenFunc ¶ added in v0.1.0
func DescendantsFunc ¶
func IsCoreFunc ¶ added in v0.2.0
func IsValidFunc ¶ added in v0.0.2
func ParentsFunc ¶ added in v0.1.0
func PlacetypesFunc ¶
Types ¶
This section is empty.
Source Files
¶
Directories
¶
| Path | Synopsis |
|---|---|
|
cmd
|
|
|
package http provides HTTP middleware methods for appending the necessary static assets and HTML resources to use the wasm binary in web applications.
|
package http provides HTTP middleware methods for appending the necessary static assets and HTML resources to use the wasm binary in web applications. |
|
package static provides an `embed.FS` containing JavaScript and WebAssembly binaries used by the go-whosonfirst-export-wasm tools and methods.
|
package static provides an `embed.FS` containing JavaScript and WebAssembly binaries used by the go-whosonfirst-export-wasm tools and methods. |